The present invention relates to wrenches, and more specifically, to a multipurpose socket wrench, which can be easily driven to rotate the workpiece with less effort.
A variety of socket wrenches have been disclosed for grasping and turning nuts, bolts, etc., and have appeared on the market. FIGS. 20 and 22 show two different socket wrenches according to the prior art. These socket wrenches are commonly comprised of a handle, and a socket adapted to rotate a bolt or nut with the handle. The handle has a driving shaft of square or hexagonal cross section perpendicularly disposed at one end. The socket has a coupling hole adapted to receive the driving shaft of the handle, and a receiving hole adapted to receive the workpiece. These conventional socket wrenches have numerous drawbacks as outlined hereinafter.    1. Because the sockets fit only particular bolts and nuts, the application range of these convention socket wrenches is limited.    2. Because the diameter of the coupling hole of the socket is shorter than the diameter of its receiving hole, driving force is not transmitted from the handle to the workpiece linearly, much effort should be employed when driving the handle to rotate the workpiece. This drawback is more apparent in the prior art socket wrench shown in FIG. 22.    3. In order to make the coupling hole, the socket must have a certain height. However, because the socket must be made having a certain height, the material cost is high. Due to this reason, the socket is heavy and expensive.